Device for trimming the edge of metal strip



April 16, 1968 H. DE CORTA DEVICE FOR TRIMMING THE EDGE OF METAL STRIPFiled April 5, 1966 5 Sheets-Sheet 1 .ZIIr

Illlllllllllllllllll \NVENTOR'.

HUBERT dc. CORTA 'TRNEYS April 16, 1968 H. DE CORTA 3,377,396

DEVICE FOR TRIMMING THE EDGE OF METAL STRIP Filed April 5, 1966 3Sheets-Sheet 2 \NVEN QRI H U BERT Ac CORTA AT QRNEIS April 16, 1968 H.DE CORTA 3,377,395

DEVICE FOR TRIMMING THE EDGE OF METAL STRIP 5 Sheets-Sheet 5 Filed April5, 1966 m m N \NYENTOR HUBERT A: CORTA RNEYS ATT United States Patent 14Claims. (Cl. 83-3) This invention relates to improvements in a devicefor trimming the edges of metal strip as this moves continuously pastthe device. It is of particular, but not exclusive, application wherecontinuous runs of welded tube are to be produced from slrip metalunwound from a coil.

As is well known, strip metal is subject to faults of three particularkinds: (a) is edges are irregular in shape and structure; (b) itslongitudinal centre line is not straight, but wavy; and, finally (c) itswid.h is not constant.

In order to render the strip more suitable for subsequent use (in makingwelded tubing, for example), it is desirable to trim the edges of thestrip, that is to say to do away with edge irregularities and also, insome cases, to make the width of the strip the same throughout. Forthis, one could use a planing machine, which cuts the moving strip.However, as the strip is not straight lengthwise, but often presentsitself like a curved sword blade,

the plane fails to bite'at some points along the edge, of

the strip while biting too deeply at others. This fault is still moreserious when the strip is covered with scale, because, after every breakin the shaving, the plane must first cut through the scale, which, owingto its abrasive nature, causes rapid wear on the tool.

It is an object of the present invention to provide an improved devicefor trimming at least one edge of a continuously advancing metal stripwhich device shall not be subject to the disadvantages referred to, atleast to the same extent as hitherto.

For this purpose, the device here proposed, which enables at least oneedge of a continuously advancing strip to be trimmed, comprises a platemember mounted so as to swing about a vertical pivot and bearing twofixed rollers at the side lying towards the edge of the strip to betrimmed. Between these rollers, a trimming or cutting tool is fitted.The plate member also carries at least one roller which is resilientlydisplaceable to push against the opposite edge of the metal strip, so asto ensure that the edge on which the tool does its work bears at alltimes against the fixed rollers.

This device makes it possible to trim the metal strip, that is to say toeliminate irregularities from one of its edges, notwithstanding thewinding nature of its longitudinal centre line. The shaving produced iscontinuous. With scaly strip, this is of particular advantage, as thetool need not cut repeatedly through the scale.

For trimming the other or opposite edge of the strip, use may be made ofa second such device, in which the positions of the fixed rollers andtool on the one hand and the moving roller or rollers on the other arereversed in relation to the longitudinal centre line of the metal strip.

It is also possible, in another embodiment of the invention, to combinetwo such devices into one, producing a piece of equipment with whichboth edges of the strip can be trimmed at once for the removal ofirregularities. To do this, all that is required is to provide a secondplate member capable of motion in relation to the first, the first onecarrying two fixed rollers with a tool between them, while the secondone, which likewise carries two fixed rollers with a tool between them,is acted on by spring means or the like tending to urge the two sets ofrollers towards each other.

In one preferred form of equipment embodying the invention principle,the cutting tool used for trimming the edges of the strip is of acircular shape generated by the revolution of a conventional cutterprofile, which, in the cutting position, has its clearance angle andangle of presentation positive and within the axis and which has itsaxis of rotation offset from the plane of the strip, so that the tool isrotated by the movement of the strip itself, thereby enabling the use ofa driving motor to be dispensed with in most cases. One advantage of acircular cutter of this kind is that it has a far longer life than thatof a conventional fixed cutter. This results in a considerable reductionin the number of production hold-ups caused by tool replacements.Moreover, when the axis of rotation of the tool lies above the plane ofmotion of the metal strip, the continuous shaving is automaticallydischarged downwards. Another advantage of this arrangement is that thezone of contact between the strip and the rotating tool, which zone liesbelow the axis of rotation of the tool, itself inclined in relation tothe direction of advance of the metal strip, gives rise to the formationof a chamfer. This chamfer is of special advantage where the strip isused for the production of welded tubes, since it is directed the rightway for the subsequent longitudinal welding of the two edges after thesehave been brought together. The angle of this charnfer can be regulatedeither by varying the distance between the axis of rotation of thecutter and the plane of the strip or by slightly inclining the axis ofrotation of the cutter to the plane of motion of the strip. Finally, thecooling of such a circular tool is very easy, as experience has shownthat a simple jet of water or other cooling liquid suffices for thepurpose.

In addition to doing away with irregularities in the edges, it may alsobe desirable to bring the strip to a constant width throughout. Theinvention also includes an apparatus with which this second operationcan be carried out in conjunction with the device or devices used fortrimming the edges.

In one form of such an apparatus, the edge-trimming devices are followedby a device comprising an additional plate member capable of swingingabout a pivot and bearing at least two fixed rollers and two movingrollers pushed towards the fixed rollers by spring action or the like, afixed tool being mounted on the plate between the moving rollers. Thetool acting on one edge of the metal strip is thus stationary inrelation to the rollers against which the other edge of the strip bears.This device may be followed by one or more similar devices, according tothe width equalization desired.

In another form of such an apparatus, one device for trimming one of theedges of a metal strip is combined in one and the same machine with adevice for reducing the strip to the same width throughout, bothoperations being carried out at once. For this purpose, all that isnecessary is to add to the device (consisting of a cutting tool mountedbetween first and second rollers carried on a movable plate, with twodis-placeable rollers pressed by springs or the like towards the firstand second rollers) a further cutting tool carried by the plate betweenthe two displaceable rollers. While the first tool serves to trim one ofthe edges, the other or further tool is used for reducing the strip tothe same width throughout.

Again, should it be desired to achieve this regularity of width byremoving equal shavings simultaneously from both edges of the strip,this can be done with a further variant of the device according to theinvention.

In this variant, the plate member which is displaceable about a pivotalaxis carries two cutting tools in fixed positions, each fitted between atrailing roller and a displaceable leading roller, the two leadingrollers, which are intended to guide the strip by its edges, beingmounted on a sysetm whereby the longitudinal centre line of the strip ismaintained substantially equidistant from the two tools.

In one form of this variant, in order to maintain the longtiudinalcentre line of the strip equidistant from the two tools, thedisplaceable rollers are mounted on articulated levers provided withtoothed sectors in mesh with each other, elastic components being usedto press these moving rollers towards each other.

Some embodiments of the invention will now be described by way ofexample, reference being made to the accompanying drawings, in which:

FIGURE 1 is a plan of one form of device for trimming one of the edgesof a metal strip in accordance with the invention;

FIGURE 2 is a cross-section taken on the line 11-11 of FIGURE 1;

FIGURE 3 is a diagrammatic plan of one form of apparatus with which ametal strip can have each edge trimmed in turn and its width made thesame throughout;

FIGURE 4 shows in diagram form a combination device for trimming bothedges of a strip simultaneously;

FIGURE 5 shows in diagram form a variant of the invention in which oneedge of a strip is trimmed at the same time as the strip is beingbrought to a uniform width throughout; and

FIGURE 6 shows in diagram form another variant, with which substantiallyequal shavings can be removed from both edges.

The device shown in plan in FIGURE 1 enables one edge of a continuouslyadvanced metal strip F to be trimmed, in order to do away withirregularities in that edge. It comprises a plate 1, which takes theform of a frame containing a substantially rectangular central slot oraperture 2. The two sides of frame 1 run parallel to the diretcion ofadvance of the metal strip and each carries a system of rollers, one tobear against the edge that is to be trimmed and the other to bearagainst the opposite edge. p The first system includes a leading roller3, which is stationary in relation to the plate but can have itsposition varied in relation to the plate. For this purpose, a spindle 4of this roller 3 is carried by a small plate mounted (dovetail-fashion,for example) in a slide 5 so that it can slide in relation to astationary block 6, fixed to plate 1. Means are provided, numberedgenerally 5', for locking the rollers spindle 4 in the desired position.

Rearwardly of the roller 3, in the direction of advance of the strip,but in the immediate vicinity of this roller, a trimming cutter 7 islocked in position. In the form illustrated, which is to be preferred,this cutting tool is a circular cutter conceived as generated by therevolution of a conventional cutting tool, that is to say that anyradial section of tool 7 is identical to the longitudinal section of aconventional cutter, with the same cutting and clearance angles etc. Thetool 7 is carried on a spindle 8 which rotates in a block 9, theposition of which in relation to plate 7 can be varied by any acceptedmethod whereby, in particular, the inclination and position of the tool7 can be varied in relation to a tangent from the roller 3 parallel tothe direction of advance of strip F. Forexample, the angular position oftool-holder block 9 can be fixed with the aid of bolts 10 screwed into aplate 11 with shims of variable thickness in between. The plate 11 ismounted (dovetail-fashion, for instance) in a slide 13, in which it islocked by some accepted means, numbered generally 14. In addition, thetool spindle 8 lies outside and preferably above the plane containingthe longitudinal centre line of the metal strip F. The spindle 8 may behorizontal or it may be slightly inclined in relation to the plane ofmotion of the strip, so as to regulate the angle of chamfer. Thedistance between the spindle 3 and the plane of the strip, measuredperpendicularly from the edge to be cut, is so pre-determined that thetranslational movement of the strip causes the tool 7 to rotate whileimposing the minimum stress on the bearings of the spindle 8.

To complete the guidance of the strip, it is desirable, as indicated inthedrawing, to provide a second roller, 15, identical to the first, thatis to say, stationary in relation to plate 1 but adjustable as to itsposition, this second roller being siuated rearwardly of the tool in thedirection of advance of strip F.

Facing the system just described, which is concerned with one edge ofthe strip, the opposite side of frame 1 carried another system,consisting either of a single roller substantially equidistant from thetwo fixed rollers 3 and 15, or, better still, as shown, two rollers 16and 17. The purpose of these rollers 16 and 17 is to apply a thrust tothe opposite edge of the strip, so as to ensure that the edge to be cutis at all times in contact with fixed rollers 3 and 15. To that end, therollers 16 and 17 may be mounted in exactly the same way as those on theside of the edge being cut, but, instead of means such as 5' beingprovided for locking the roller-holding plate in a slide 5, as in theformer case, a free sliding action is provided by spring means, such as,for example, an assembly of spring washers 18 which urge thedisplaceable rollers 16 and 17 towards fixed rollers 3 and 15respectively.

One feature of the invention is that plate 1 is free to swing about afixed vertical pivot 21. This fixed pivot can be used for the trimmingof strips of various widths. In other words, the position chosen forthis pivot may be such that it lies substantially on the longitudinalcentre line of a strip of average width, whereas, over a wide range ofstrip widths, the pivot will no longer lie on this line, but that willnot interfere with the proper functioning of the device. It should benoted that the device enables a consant shaving to be removed, whateverthe width of the 'strip.

The mode of operation of the device described above will be readilyunderstood. In particular, no matter how the strip F winds within itsown plane, the cutter 7 engages with the edge to be trimmed according tothe relative positions of this cutter and of fixed rollers 3 and 15,against which the sheet is constantly held. A continuous shaving is thusremoved and automatically discharged through the central opening 2 inframe 1.

Similarly, to trim the other edge of the strip, a second device,numbered generally 22 in FIGURE 3, may be provided. This is the mostconvenient method where considerations of space are not of paramountimportance; for, where the two edges are trimmed by two successivedevices, there is no jarring during the passage of the transverse weldsnecessarily used for joining two strips end to end.

On the other hand, if it is necessary to reduce the amount of spacetaken up by the equipment, two devices of the kind shown in FIGURE 1 canbe combined to form a single installation such as that illustrateddiagrammatically in FIGURE 4. In this arrangement, the plate 1 ispivoted at 21 and carries the two rollers 3 and 15, between which is acutting tool 7, preferably circular and of the rotary type. The rollersand the tool are stationary but can be adjustably fixed in variouspositions in relation to the plate. The apparatus is completed bya'secend plate 23, which is movable with respect to the first, forexample by virtue of its being mounted on suitable slides or articulatedat the pivot 21. This second plate 23 carries fixed rollers, '24 and 25,between which is fitted a tool 26, identical to the tool 7. Theserollers 24 and 25 and the tool 26 are stationary in relation to thissecond plate 23, but their position can be varied. In addition,components such as springs 27 or the like, which bear against plate 1,act on the plate 23 so as to thrust the assembly 24/25/26 on one sidetowards the assembly 3/7/ 15 on the other side. This amounts to sayingthat the two fixed rollers associated with a tool on one plate have thesame function, in relation to the corresponding fixed rollers on theother plate, as that of the moving rollers in the previous case,numbered r16 and 17 in FIGURE 1. This apparatus thus enables both edgesof the strip to be trimmed simultaneously,

In addition to trimming the edges, it may be necessary to bring thestrip to the same width throughout its length. This can be done with theaid of a device separate from that or those used for the edge trimming.For example, as in the case shown in FIGURE 3, a device such as thatnumbered generally at may be fitted to follow the two edge trimmers.This device comprises a'plate 31, pivoted at 34. For one of the edgesalready trimmed, the plate 31 carries two fixed rollers 35 and 36. Forthe other edge, it carries two displaceable rollers 37 and 38, acted onby resilient means such as springs 39. Between the displaceable rollers37 and 38, a tool 40 is locked in position. This may be a rotarycircular cutter or a simple conventional cutter, since it is working ona readytrimmed face and is thus no longer called upon to cut through thescale that causes such considerable wear.

In this way the tool 40, by acting on one edge at a constant distancefrom the other edge, which is pressed against the rollers 35 and 36,doe-s indeed produce a strip of constant width. This device 30 maynaturally be followed by one or more similar devices, according to thewidth of shavings having to be removed to produce this constant width.

It is also possible to employ a combination installation with which theedge trimming and width adjustment can be efiected simultaneously. Aninstallation of this kind is shown diagrammatically in FIGURE 5. Itcomprises a plate 1 pivoted about a fixed point 21, on which plate ismounted a combination of two rollers 3 and 15, between which a cutter 7is fitted. Facing these fixed rollers are two displaceable rollers 16and .17, spring-loaded by means such as 18, the assembly being so faridentical to that shown in FIGURE 1. In addition, however, a cutter 40'is fixed to plate 1 between the displaceable rollers 16 and .17. It willbe apparent that this equipment combines the single edge-trimming deviceshown in FIGURE 1 with a device for bringing the strip to a constantwidth, such as the one numbered 30 in FIGURE 3.

In the variant illustrated in FIGURE 6, the plate 41, again has a pivot,44.

In order to remove shavings which are substantially equal at any givenmoment from both edges, for the purposes of reducing the strip to aconstant width, the plate 41 carries two cutters 45 and 45, each ofwhich cuts one edge of the strip. These should preferably be of therotary type already described, their position being adjustable but fixedin relation to the plate. Each cutter lies between a trailing roller 46or 46' respectively, the position of which is adjustable but is fixed inrelation to the plate, and a leading roller 47 or 47 respectively whichis displaceable relative to the plate.

So that each cutter shall have substantially no more than half theexcess width to remove from the strip, the rollers 47 and 47 are carriedon arms or levers 48 and 48, which are pivoted at fixed points 49 and49' respectively and bear toothed sectors 50 and 50 respectively, thesectors being in mesh with each other. In addition, resilient means suchas springs 51 and 51 exert a thrust tending to move the displaceablerollers 47 and 47' towards each other.

This toothed sector arrangement is naturally only one example of how theprinciple can be put into eifect. The specialist will have no diflicultyin devising other equivalent means for ensuring that the longitudinalcentre line is kept equidistant from the two tools 45 and 45', carriedby the plate.

The examples described can naturally be modified in a number of wayswithout going beyond the scope of the invention.

Thus, for instance, it is possible in all cases to use a conventionalfixed cutter instead of the rotary circular one described, though thelatter is preferred wherever the tool is called upon to cut throughscale. Further variants apart from those described here might also bedesigned; for example, one edge could be cleaned up with a device suchas that shown in FIGURE 1, the other edge being cleaned and the width ofthe strip made uniform by means of a device of the kind showndiagrammatically at 30 in FIGURE 3.

What is claimed is:

1. A device for trimming at least one edge of a continuously advancingmetal strip comprising a plate member displaceable about a pivotal axis,first and second rollers mounted on the plate member in fixedrelationship thereto and spaced lengthwise of the direction of advanceof the strip for engagement with one longitudinal edge of the strip, acutting tool mounted on the plate member intermediate said first andsecond rollers, at least one further roller carried on said plate memberand spaced from said first and second rollers in the direction of widthof the strip and engageable with the other longitudinal edge of thestrip and spring means urging said one further roller towards said firstand second rollers to draw said first and second rollers into engagementwith said one longitudinal edge of the strip.

2. A device according to claim 1 wherein said first and second rollersare adjustably mounted on said plate memher.

3. A device according to claim 1 wherein said first and second rollersare mounted on said plate member for adjustment in the direction of thewidth of the strip.

4. A device according to claim 1 wherein the cutting tool is a circularcutter rotatably mounted on the plate member.

5. A device according to claim 4 wherein the shape of the circularcutter is generated as a body of revolution of a conventional cutter.

6. A device according to claim 4 wherein the circular cutter is mountedfor rotation about an axis oflset from the general plane of the strip soas to be rotated by engagement with and advancement of the strip.

7. A device according to claim 6 wherein the axis of rotation of thecircular cutter is disposed above the general plane of the strip and theplate member is formed with a slot located to receive and permit theescape downwardly of the continuous shaving produced by the cutter.

8. A device according to claim 1 including a second further rollerspaced from said one further roller in the direction of advance of thestrip and resiliently urged towards said first and second rollers forengagement with said other longitudinal edge of the strip.

9. A device according to claim 8 including a further plate memberdisplaceably mounted on said first-mentioned plate member and spacedfrom said first and second rollers in the direction of width of thestrip, said one and said second further rollers being carried on saidfurther plate member and said further plate member being resilientlyurged towards sai-d first and second rollers.

10. A device according to claim 9 including a second cutting toolcarried on said further plate member intermediate said one and saidsecond further rollers whereby said one and said other longitudinaledges of the strip may be trimmed simultaneously by said cutting tools.

11. Apparatus for trimming at least one edge of a continuously advancingmetal strip comprising at least one device according to claim 1 followedin the direction of advance of the strip by a further device comprisingan additional plate member displaceable about a pivotal axis, first andsecond additional rollers carried on said additional plate member andspaced in the direction of advance of the strip and engageable with oneof said one and said other longitudinal edges of the strip, first andsecond additional further rollers displaceably mounted on saidadditional plate member and spaced from said first and second additionalrollers in the direction of Width of the strip, means resiliently urgingsaid first and second additional rollers into engagement with the otherof said one and said other longitudinal edges of the strip and anadditional cutting tool disposed between said first and secondadditional further rollers.

12. Apparatus according to claim 11 including a further cutting toolcarried on said plate member and disposed rearwardly of said one furtherroller considered in the direction of advance of the strip forengagement with said other longitudinal edge of the strip.

13. A device for simultaneously cutting both longitudinal edges of acontinuously advancing metal strip comprising a plate memberdisplaceable about a pivotal axis, a pair of opposed guide rollersmounted on the plate member and disposed one on either side of the stripand resiliently urged into engagement with the respective longitudinaledges of the strip, a further pair of opposed rollers disposedrearwardly of the guide rollers considered in the direction of advanceof the strip and engageable with the respective longitudinal edges ofthe strip, and a separate cutting tool disposed between each guideroller and the corresponding one of the further rollers the guiderollers being operable to maintain the longitudinal centre line of thestrip equidistant from both cutting tools.

14. A device according to claim 13 wherein a pair of levers is pivotallymounted on the plate member and each lever carries a separate one of theguide rollers, a separate toothed sector is carried by each lever suchthat said sectors are in mesh with each other and spring means isprovided operable to urge the guide rollers towards each other and intoengagement with the longitudinal edges of the strip.

References Cited 15 UNITED STATES PATENTS 1,967,262 7/1934 Robinson eta1 83-432 X 2,859,813 11/1958 Klotz 83-412 X 3,110,208 11/1963 Mitchellet a1 83425 X ANDREW R. JUHASZ, Primary Examiner.

1. A DEVICE FOR TRIMMING AT LEAST ONE EDGE OF A CONTINUOUSLY ADVANCINGMETAL STRIP COMPRISING A PLATE MEMBER DISPLACEABLE ABOUT A PIVOTAL AXIS,FIRST AND SECOND ROLLERS MOUNTED ON THE PLATE MEMBER IN FIXEDRELATIONSHIP THERETO AND SPACED LENGTHWISE OF THE DIRECTION OF ADVANCEOF THE STRIP FOR ENGAGEMENT WITH ONE LONGITUDINAL EDGE OF THE STRIP, ACUTTING TOOL MOUNTED ON THE PLATE MEMBER INTERMEDIATE SAID FIRST ANDSECOND ROLLERS, AT LEAST ONE FURTHER ROLLER CARRIED ON SAID PLATE MEMBERAND SPACED FROM SAID FIRST AND SECOND ROLLERS IN THE DIRECTION OF WIDTHOF THE STRIP AND ENGAGEABLE WITH THE OTHER LONGITUDINAL EDGE OF THESTRIP AND SPRING MEANS URGING SAID ONE FURTHER ROLLER TOWARDS SAID FIRSTAND SECOND ROLLERS TO DRAW SAID FIRST AND SECOND ROLLERS INTO ENGAGEMENTWITH SAID ONE LONGITUDINAL EDGE OF THE STRIP.